Computerized analysis of the transmural distribution of myocardial echo-contrast effect

The authors describe a method for the automatic analysis of the transmural distribution of the myocardial echo contrast effect. In anesthetized open-chest dogs the contrast agent SHU-454 was bolus-injected into the aortic root during short-axis 2-D echo, both at baseline and during coronary stenosis. End-diastolic echo images were digitized offline. In the first image of the sequence, the left-ventricular (LV) inner and outer myocardial edges were digitized. From the gravity center of the LV cavity a grid was automatically drawn to divide the myocardium into 16 equal sectors, and each sector into three layers. For each layer, the mean video density and the area were measured, sorted by sector and layer, and transferred online to a personal computer for further analysis. This system allows an automatic analysis of the distribution of the myocardial echo contrast effect, both in the space and in the time domain. Since the spatial distribution of the contrast effect parallels the distribution of coronary blood flow, this method might be a tool for studying the transmural distribution of coronary blood in vivo